melinite

LInux

Three system configuration parameters must be set to support a large number of open files and TCP connections with large bursts of messages. Changes can be made using the /etc/rc.d/rc.local or /etc/sysctl.conf script to preserve changes after reboot.

1. /proc/sys/fs/file-max: The maximum number of concurrently open files.

fs.file-max = 1000000

2. /proc/sys/net/ipv4/tcp_max_syn_backlog: Maximum number of remembered connection requests, which are still did not receive an acknowledgment from connecting client. The default value is 1024 for systems with more than 128Mb of memory, and 128 for low memory machines.

net.ipv4.tcp_max_syn_backlog = 3240000

3. /proc/sys/net/core/somaxconn: Limit of socket listen() backlog, known in userspace as SOMAXCONN. Defaults to 128.

net.core.somaxconn = 3240000

melinite

#!/bin/sh

# It seems it's very hard to set resample output quality with Ghostscript.
# So instead rely on `prepress` preset parameter to select a good /QFactor
# and override the options we don't want from there.

gs \
  -o resampled.pdf \
  -sDEVICE=pdfwrite \
  -dPDFSETTINGS=/prepress \

melinite

#!/bin/bash
#Variable for choosing the file

FileInput=$1
FileOutput=$2
#GS compression of the pdf

gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/default -dNOPAUSE -dBATCH -dDetectDuplicateImages -dCompressFonts=true -r300 -sOutputFile="$FileOutput" "$FileInput"

mv "$FileOutput" "$FileInput"

melinite

Understanding Your Google Cloud Costs

# Analyzing Billing Data with BigQuery
SELECT * FROM `billing_dataset.enterprise_billing` WHERE Cost > 0
SELECT Line_Item FROM `billing_dataset.enterprise_billing` GROUP BY Line_Item
SELECT Line_Item, COUNT(*) as NUM FROM `billing_dataset.enterprise_billing` GROUP BY Line_Item
SELECT Project_ID, COUNT(*) as num FROM `billing_dataset.enterprise_billing` GROUP BY Project_ID
SELECT SUM(cost) as Cost, Project_Name FROM `billing_dataset.enterprise_billing` GROUP BY Project_Name

# Visualizing Billing Data with Data Studio

melinite

security and hardening options for systemd service units

A common and reliable pattern in service unit files is thus:

NoNewPrivileges=yes
PrivateTmp=yes
PrivateDevices=yes
DevicePolicy=closed
ProtectSystem=strict

melinite

#
# Wide-open CORS config for nginx
#
location / {

     if ($request_method = 'OPTIONS') {

        add_header 'Access-Control-Allow-Origin' '*';
        
        #

melinite

#!/bin/bash
# 
# Script to create full and incremental backups (for all databases on server) using innobackupex from Percona.
# http://www.percona.com/doc/percona-xtrabackup/innobackupex/innobackupex_script.html
#
# Every time it runs will generate an incremental backup except for the first time (full backup).
# FULLBACKUPLIFE variable will define your full backups schedule.
# 
# 2012 Brad Svee modified to try to use xbstream
# (C)2012 Atha Kouroussis @ Vurbia Technologies International Inc.

melinite

The fastest remote directory rsync over ssh archival I can muster (40MB/s over 1gb NICs)

This creates an archive that does the following:

rsync (Everyone seems to like -z, but it is much slower for me)

• a: archive mode - rescursive, preserves owner, preserves permissions, preserves modification times, preserves group, copies symlinks as symlinks, preserves device files.
• H: preserves hard-links
• A: preserves ACLs

melinite

#! /bin/bash

sudo apt-get update
sudo apt-get install -y software-properties-common debconf-utils
sudo add-apt-repository -y ppa:webupd8team/java
sudo apt-get update
sudo echo "oracle-java8-installer shared/accepted-oracle-license-v1-1 select true" | sudo debconf-set-selections
sudo apt-get install -y oracle-java8-installer

melinite

#!/bin/bash

SENDGRID_API_KEY=""
EMAIL_TO=""
FROM_EMAIL=""
FROM_NAME=""
SUBJECT=""

bodyHTML="<p>Email body goes here</p>"